I have to wonder if the folks saying take something showing she's been married and will be OK have any practical experience with flying internationally with a passport not matching a ticket.

It probably would be OK in getting out of the US. I actually saw that happen back in November and because a MIL booked a ticket wrong and my local airport security was letting someone fly domestically but needed extra security. (it was the woman at the TSA gate right in front of me and played out in front of me)

My fear would not be with the magical piece of paper getting out of the country but back IN the good ole US.

I have had a name change. My passport reflects that. There's a notation see such and such page on the back and it shows bearer's name was changed to yxz. I had a great deal of trouble when trying to leave Poland. The check in agent and then security agent spoke little to no English and couldn't figure it out because the notation is at the bottom of the page in small letters saying there is an amendment and turn to such and such page. They just knew to match and couldn't read/understand the words to go to such and such page due to name change.

It took a while, was scary at the time, they didn't understand me and I didn't understand them. I eventually was able to board my plane. While traveling in October to and from Canada, I had agents question the issue. I had one agent in ORD tell me I wouldn't be able to board because my passport didn't match my boarding pass until I pointed to the amendment, flipped to the right page, grinned and she meekly let me board. My point is I wouldn't assume that some magical piece of paper will help a bride out. It might work. But it could cause time, trouble and frustration that no bride should have to endure on her honeymoon.

It only takes one TSA agent or one foreign agent on a power trip or going by the book to wreck this apple cart

I don't know what the actual solution is but I strongly advise fixing before flying and not hope a magical piece of paper will fix the issue.